condition mean min max ZT0-3 933.603478 933.603478 933.603478 ZT4-7 740.6823770000001 740.6823770000001 740.6823770000001 ZT8-11 777.7121265000001 777.7121265000001 777.7121265000001 ZT12-15 793.710752 793.710752 793.710752 ZT16-19 951.8927135000001 951.8927135000001 951.8927135000001 ZT20-23 635.4489424999999 635.4489424999999 635.4489424999999